Key Laboratory of Molecular Biophysics of Chinese Ministry of Education, College of Life Science and Technology, Huazhong University of Science and Technology-HUST, Wuhan, China.
PLoS One. 2013 Jun 10;8(6):e65120. doi: 10.1371/journal.pone.0065120. Print 2013.
WRKY transcription factors are reported to be involved in defense regulation, stress response and plant growth and development. However, the precise role of WRKY transcription factors in abiotic stress tolerance is not completely understood, especially in crops. In this study, we identified and cloned 10 WRKY genes from genome of wheat (Triticum aestivum L.). TaWRKY10, a gene induced by multiple stresses, was selected for further investigation. TaWRKY10 was upregulated by treatment with polyethylene glycol, NaCl, cold and H2O2. Result of Southern blot indicates that the wheat genome contains three copies of TaWRKY10. The TaWRKY10 protein is localized in the nucleus and functions as a transcriptional activator. Overexpression of TaWRKY10 in tobacco (Nicotiana tabacum L.) resulted in enhanced drought and salt stress tolerance, mainly demonstrated by the transgenic plants exhibiting of increased germination rate, root length, survival rate, and relative water content under these stress conditions. Further investigation showed that transgenic plants also retained higher proline and soluble sugar contents, and lower reactive oxygen species and malonaldehyde contents. Moreover, overexpression of the TaWRKY10 regulated the expression of a series of stress related genes. Taken together, our results indicate that TaWRKY10 functions as a positive factor under drought and salt stresses by regulating the osmotic balance, ROS scavenging and transcription of stress related genes.
WRKY 转录因子被报道参与防御调控、应激响应和植物生长发育。然而，WRKY 转录因子在非生物胁迫耐受性中的精确作用尚不完全清楚，尤其是在作物中。在本研究中，我们从小麦（Triticum aestivum L.）基因组中鉴定和克隆了 10 个 WRKY 基因。TaWRKY10 是一个受多种胁迫诱导的基因，被选为进一步研究的对象。TaWRKY10 受到聚乙二醇、NaCl、冷和 H2O2 的处理而上调。Southern 印迹的结果表明，小麦基因组含有三个 TaWRKY10 拷贝。TaWRKY10 蛋白定位于细胞核内，作为转录激活因子发挥作用。在烟草（Nicotiana tabacum L.）中过表达 TaWRKY10 导致增强了干旱和盐胁迫耐受性，主要表现在这些胁迫条件下，转基因植物的发芽率、根长、存活率和相对含水量增加。进一步的研究表明，转基因植物还保留了更高的脯氨酸和可溶性糖含量，以及更低的活性氧和丙二醛含量。此外，过表达 TaWRKY10 调节了一系列与胁迫相关基因的表达。总之，我们的结果表明，TaWRKY10 通过调节渗透平衡、ROS 清除和与胁迫相关基因的转录，在干旱和盐胁迫下作为一个正调控因子发挥作用。
